Numerical Modeling of a Salinity Intrusion Barrier Saltwater Intrusion Prevention System

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Numerical Modeling of a Salinity Intrusion
BarrierSaltwater Intrusion Prevention System
Developed Through a Cooperative Research
Development Agreement Patented Technology owned
by Saltwater Separation, LLC
Saltwater Separation, LLC Team E. Robert
Kendziorski robertk_at_saltwaterseparation.com 949.67
7.1991 Charles H. Tate, P.E. ctate_at_saltwatersepara
tion.com 601.218.2173

• ERDC-CHL Team
• Jose E. Sanchez, P.E.
• Robert Bernard, PhD
• Robert.S.Bernard_at_usace.army.mil
• Phu Luong, PhD
• Phu.V.Luong_at_usace.army.mil

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Salinity Intrusion Barrier System
OUTLINE

• Challenges
• Cooperative Research and Development Agreement
  (CRADA)
• US Army Engineer Research and Development Center
  Coastal and Hydraulics Laboratory (ERDC-CHL)
• PAR3D
• Miraflores Locks
• Simulation basis
• Experiments
• Results
• Recommendations and Conclusions

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Salinity Intrusion Barrier System
CHALLENGES

• Miraflores Lake brackish condition
• Current estimates of 1ppt concentration (ERDC-CHL
  2000 study)
• No salinity intrusion barrier or system in place
• Quality issues for some uses
• Increased traffic demand
• Current operations general range between 30 and
  40 ships per day
• Future expectations of up to 53 ships per day
• Unsteady flow in the downstream lock approach
  conditions during emptying cycle
• Inconsistent navigation condition (1 out of 30
  may impact the lock structure, as per WPSI)
• Possible Canal expansion

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Salinity Intrusion Barrier System
CRADA

• What is it?
• Cooperative Research and Development Agreement
• Benefits
• Allows USACE to partner with other organizations
• Shares information, knowledge, discoveries
• Parties involved
• US Army Engineer Research and Development Center,
  Coastal and Hydraulics Laboratory
• Water Processing Systems Incorporated

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Salinity Intrusion Barrier System
ERDC-CHL

• Expertise
• 75 years experience in physical and numerical
  hydraulic modeling
• 250 personnel
• 140 Engineers and Scientists
• 56 with PhDs
• 60 with MS degrees
• Resources
• Many numerical models available
• PAR3D chosen
• High Performance Computing Center on site
• Among the top 10 in the world

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Salinity Intrusion Barrier System
PAR3D

• What is it?
• 3-dimensional incompressible flow numerical model
• Accommodates
• Deforming grids
• Free-surface displacement
• Multiple processors
• Capabilities include
• Heat and dissolved-gas transfer and transport
• Salinity transport
• Temperature stratification and mixing
• Sediment and biomass transport (with oxygen
  demand)
• Turbulence modeling including buoyancy
• Flow driven by bubble plumes and mechanical
  mixers

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Salinity Intrusion Barrier System
PAR3D (CONTINUED)

• Governing equations
• Navier-Stokes equations for incompressible flow
• K-Epsilon turbulence model
• Pneumatic injection specialty
• Published in Applied Mathematical Modeling
• Independent peer review for application to
  independent experimental data, 2000
• Previous applications
• Taylorsville Lake intake structure, internal flow
  in the structure
• WES Riprap Test Facility, open-channel flow
  around a bend
• McCook Reservoir (in design), pneumatic bubble
  plume application

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Salinity Intrusion Barrier System
MIRAFLORES LOCKS
INLAND SIDE
OCEAN SIDE
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Salinity Intrusion Barrier System
MIRAFLORES LOCKS
model grid area
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Salinity Intrusion Barrier System
INITIAL SIMULATION BASIS

• Average depth (50-ft)
• No tidal action
• No vessel
• Approximate bathymetry (el. 50ft)
• Lock exit structure modeled
• Channel width approximated (110 to 220-ft)
• Starting salinity
• 10 ppt DS of miter gates (1000-ft stretch)

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Salinity Intrusion Barrier System
MODEL
Pacific Ocean
Guide wall
Miter gates

• Total length 1000-ft
• 110-ft wide
• 50-ft deep

Wing wall
100-ft
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Salinity Intrusion Barrier System
Model Simulations

• Existing conditions without salinity barriers
• During emptying cycle
• Simplified lock release (steady state outflow)
• 15 min cycle with 3kcfs flow rate
• 20 min after emptying cycle ends
  (re-stratification)
• Effects of bubble curtains
• With/without pneumatic injection
• Bubble curtain setup
• 1 bubbler 400-ft from miter gates (WPSI
  feasibility report)
• 2 bubble curtains (100 200-ft from each other)
• 4 bubble curtains (100-ft from each other)
• 8 bubble curtains (50-ft from each other)
• Fresh water injection rates with 4 bubble curtains

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Salinity Intrusion Barrier System
EXISTING CONDITIONS
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Salinity Intrusion Barrier System
BUBBLE CURTAINS vs. NO CURTAINS
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Salinity Intrusion Barrier System
FOUR BUBBLE CURTAINS 1100 scfm/curtain, 563cfs
fresh water, 3hr animation (10min intervals)
water injection
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Salinity Intrusion Barrier System
FOUR BUBBLE CURTAINS 1100 scfm/curtain, 563cfs
fresh water, 9hr simulation
water injection
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Salinity Intrusion Barrier System
Water injection rates (4 bubble curtain design)
Qw inj (cfs) fresh water (0 ppt) Time for lt 1ppt 100-ft from gates (50-ft deep)
563 180 min
885 90 min
1198 60 min
1709 60 min
1812 60 min
Time reflects salinity concentration at 100-ft
from miter gates only. Lower concentrations were
indicated further downstream sooner.
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Salinity Intrusion Barrier System
ADDITIONAL SIMULATION BASIS

• Tidal fluctuations
• Max depth 64ft
• Min depth 44ft
• Vessel exiting lock chamber
• With propeller action
• Without propeller action
• Stratified salinity distribution

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Salinity Intrusion Barrier System
Tidal fluctuation comparison
Qw inj (cfs) fresh water (0 ppt) Time for lt 1ppt 100-ft from gates (44-ft deep) Time for lt 1ppt 100-ft from gates (50-ft deep) Time for lt 1ppt 100-ft from gates (64-ft deep)
563 120 min 180 min 270 min
1812 50 min 60 min 80 min
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Salinity Intrusion Barrier System
Ship and propeller mixing characteristics

• Ship Model
• Dense grid
• 2000-ft channel
• Starting at US miter gates
• Divided into 100-ft cells
• Depth 50 ft
• Panamax type ship
• 965l x 106w x 39.5d (centered in channel
  exiting lock chamber)
• 26-ft diameter propeller helix
• 20,000 hp
• Simulation
• Initial conditions
• 5 ppt starting 200-ft downstream of ship
• 1 ppt inside of lock chamber
• 563 cfs fresh water injection 100-ft from DS
  miter gates
• 4 bubble curtain design

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Salinity Intrusion Barrier System
Ship and propeller mixing characteristics
Ship only
Pacific Ocean
Stern
Bow
Ship
lt 1 ppt
Ship with motor in operation
lt 1 ppt
563 cfs fresh water injection, 1100 scfm/curtain
1hr simulation Initial condition 5 ppt
starting 200-ft downstream of ship
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Salinity Intrusion Barrier System
Recommendations and Conclusions

• Conclusions
• Best design tested 4 bubble plumes at 1100
  standard cfm/location with minimum 563 cfs fresh
  water inflow
• More air flow does not improve performance
• More air injection points does not improve
  performance
• Higher water flow rates do improve performance,
  up to a certain limit
• Tidal fluctuations have minimal impacts on
  performance
• Ship and propeller have minimal impacts on
  performance
• Recommendations
• 2D physical tests for salinity transfer at bubble
  plumes
• Experiments to study downstream conditions during
  emptying cycle (turbulent currents baseline
  conditions)